The present invention relates to an apparatus and method for automatically controlling a semiconductor manufacturing process in a semiconductor factory automation system, capable of improving a manufacturing efficiency and yield.
A semiconductor device is generally manufactured on a semiconductor wafer through various unit processes, e.g., a photolithography process, an etching process, a thin film process and a diffusion process. A plurality of process equipments are used in each unit process. Generally, each unit process is typically performed based on a predetermined number of semiconductor wafers, referred to as a lot.
In manufacturing the semiconductor device, however, an abnormally manufactured lot may occur which has a process result data exceeding or falling below a predetermined level required in a lot specification. The abnormally manufactured lot may occur due to a problem of a lot itself, a problem of equipment conditions, a problem of manufacturing steps and the like.
A method for controlling a semiconductor manufacturing process by failure analysis feedback is disclosed in U.S. Pat. No. 5,923,553 issued to Yi, filed on Oct. 5, 1996. The method includes the steps of: a) the establishing a monitoring database with abnormal process condition data, the abnormal process condition data being obtained by a correlation between a yield for each manufactured lot and corresponding process conditions for semiconductor equipment when the yield is lowered or semiconductor equipment malfunctions have occurred; b) establishing an equipment data base by obtaining real-time process conditions for on-line semiconductor equipment; c) comparing the real-time process conditions for on-line semiconductor equipment with the abnormal process conditions of the monitoring data base; and d) stopping the operation of the on-line semiconductor equipment when differences between the real-time and abnormal process conditions fall below a predetermined level.
At this time, Yi""s patent discloses that the causes of the abnormally manufactured lot is the equipment or the process condition malfunction. For solving the problem, the operation of the corresponding equipment is stopped. However, the abnormally manufactured lot may mainly occur due to the processed lot itself.
As can be seen above, however, even when a lot is abnormally manufactured in the middle of the lot process, a following process is continued without considering the abnormally manufactured lot until a completion of the entire lot process. Therefore, a manufacturing efficiency is reduced.
It is, therefore, an object of the present invention to provide an apparatus and method for automatically controlling a semiconductor manufacturing process in a semiconductor factory automation system, capable of improving an efficiency in manufacturing semiconductor devices.
In accordance with an aspect of the present invention, there is provided an apparatus for automatically controlling a semiconductor manufacturing process in a semiconductor factory automation system, comprising: a common communication line; a plurality of equipments, coupled to the common communication line, each processing a lot; a plurality of equipment control means, each converting command message from an exterior into command to control each equipment; a plurality of test equipments, each testing the processed lot to generate a lot process data; a plurality of test equipment control means, each receiving the lot process data to transfer the lot process data; a storage means for storing the lot process data and a lot specification data, respectively; a comparison means, coupled to the common communication line, for comparing the lot process data with the lot specification data to determine whether a difference between the processed lot data and the lot specification data exceeds or falls below a predetermined range, wherein if the difference exceeds or falls below the predetermined range, the comparison means generates a first message representing an occurrence of an abnormally manufactured lot; and a transaction generation means, coupled to the common communication cable, for generating a first transaction in response to the first message, the first transaction representing that the lot is abnormally manufactured, wherein a next lot process to the abnormally manufactured lot is prevented.
In accordance with another aspect of the present invention, there is provided a method for automatically controlling a semiconductor manufacturing process in a semiconductor factory, comprising the steps of: a) receiving a lot specification data and a lot process data; b) comparing the lot specification data with the lot process data to determine whether a difference between the lot specification data and the lot process data is within a predetermined range; c) if a difference between the lot specification data and the lot process data exceeds or falls below a predetermined range, generating a first message representing an occurrence of an abnormally manufactured lot; d) generating a first transaction in response to the first message, the first transaction representing that the lot is abnormally manufactured; and e) storing the first transaction into a storage means, wherein a next lot process to the abnormally manufactured lot is prevented.